A Revision of the New World Speciesof the Shore-Fly Genus Nostima Coquillett(Diptera: Ephydridae)

Abstract

Thirty-eight New World speciesare revised, including 21 new species that are described (type locality in parentheses): Nostimaatriscuta (Jamaica. Portland: Crystal Springs (18°12.5'N, 76°37.9'W)), N. cinnamea (GrandBahamas Island. Freeport), N. duaguttata (Costa Rica. Puntarenas: Rincon (5 km S; 8°42.1'N,83°30.8'W; 95 m)), N. footei (Panama. Canal Zone: Balboa), N. franciscana (Jamaica. St.Anns: Runaway Bay), N. lineata (Dominica: Layou (5 km E)), N. lucida (Bolivia. La Paz: Apa(8 km S Chulumani; 16°22'S, 67°30.4'W; 1960 m)), N. lutea (St. Vincent: Kingstown BotanicalGarden), N. maculata (Argentina. Tucuman: La Cavera), N. magnifica (Ecuador. Chimborazo:Naranjapata Chilicay), N. melina (Panama. Canal Zone: Kobbe Beach), N. negruzca(Grenada. St. John: Concord Falls (12°07.1'N, 61°43'W)), N. simuliflavida (Dominica. CabritSwamp), N. spinosa (Bermuda. Paget Parish: Botanical Gardens), N. stellata (Ecuador. Orellana:Rio Tiputini (0°38.2'S, 76°8.9'W)), N. tresguttata (Ecuador. Napo: Baeza (17 km S; 1815m)), N. velutina (Mexico. Chiapas: San Cristobal de Las Casas (2160 m)), N. williamsi (CostaRica. Alajuela: San Mateo, Higuito), N. xenohypopia (Dominican Republic. Pedernales: Sierrade Baoruco, Las Abejas (1300 m)), N. xenoptera (Costa Rica. Puntarenas: Rinc6n (3 km SW,9°55'N, 84°13'W, 10 m)), N. ypsilona (Costa Rica. Puntarenas: Rincon (3 km SW, 9°55'N,84°13'W, 10 m)). This study revealed the species-group Nostima niveofasciata Cresson (1947)is synonymous with Nostima canens Cresson (1941).The cladistic analysis was based upon 10 morphological characters. An analysis using"implicit enumeration" (ie-) of Hennig86 resulted in a cladogram of minimal length. This cladogramhas a length of 16 steps, a consistency index of 1.0, and a retention index of 1.0. Fromthe cladogram (Figure 255) and supporting synapomorphies, the following hypotheses can bemade: (1) Nostima is monophyletic; (2) Nostima and Garifuna form a monophyletic lineage(supported by three synapomorphies); (3) Garifuna is the immediate sister group of Nostima,and Philygria forms a clade immediately basal to the common lineage of Nostima and Garifuna;and (4) New World species of Nostima are provisionally arrayed into five lineages. Someof these lineages apparently demonstrate a speciation pattern in which peripheral or isolatedspecies diverged from more widely distributed species.Keys to the tribes and genera of Ilytheinae, as well as to the New World species of Nostima,are provided. Distribution maps are also produced for the New World species.